Space telegraphy.



PATENTED OCT. 24, 1905.

J. S. STONE.

SPACE TELEGRAPHY.

APPLICATION FILED NOV. 25. 1903. RENEWED AUG. 14,1905.

TINTTED STATES PATENT OFFICE.

JOHN STONE STONE, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNOR TO WILLIAM W.SWAN, TRUSTEE, OF BROOKLINE, MASSACHUSETTS.

SPACE TELEGRAPHY.

Specification of Letters Patent.

Patented Oct. 24, 1905.

Application filed November 25, 1903. Renewed August 14, 1905. Serial No.274,238.

To (ZZZ whom it 'mctg concern:

Be it known that I, JOHN STONE STONE, a citizen of the United States,and a resident of Cambridge. in the county of Middlesex and State ofMassachusetts, have'invented a certain new and useful Improvement inSpace lelegraphy, of which the following is a specification.

My invention relates to the art of transmitting intelligence from onestation to another by means of electromagnetic waves without the use ofwires to guide the waves to their destination; and it relates moreparticularly to the system of such transmission in which theelectromagnetic waves are developed by producing electric vibrations inan elevated conductor, preferably vertically elevated.

In my Letters Patent No. 714,756, Dec. 2, 1902, and in other LettersPatent. I have described a system of selective electric signaling inwhich forced simple harmonic electric vibrations of definite freq uencyare developed in an elevated conductor by associating the latter with asonorous or persistently oscillating circuit capable of developing likevibrations of corresponding frequency when its electrical equilbrium isdisturbed. In this system of selective space telegraphy an alternatingcu rrent generator or similar source of periodically varying electromotive force is employed to charge a condenser in the sonorous circuitan d this condenser discharging across a spark gap gives rise to a trainof electric oscillations in said circuit which, by virtue of theinductance of the circuit, may be very persistent. The forced electricvibrations developed in the elevated conductor cause the radiationtherefrom of simple harmonic electromagnetic Waves of correspondingfrequency which develop simple harmonic electric vibrations in theelevated conductor at a receiving station. The electric vibrations sodeveloped are conveyed to a closed resonant circuit associated with saidelevated conductor and as these oscillations persist. as above stated,for a relatirely great length of time, the amplitude of the vibrationsdeveloped in the resonant circuit is greatly increased because of theability of a resonant circuit to co-ordinate the amplitudes of theoscillations of the frequency to which it is attuned. This persistencyof electric oscillation in a resonant circuit has long been recognizedas prerequisite to the amplification by such clrcuit of the amplitude ofthe oscillations of the frequency to which it is attuned, and theinability to produce such persistency of electric oscillation has beenone of these oscillations falls to th of its initial amplitude.

' In the drawings which accompany and form a part of this specification,the Fig. illustrates in diagram an arrangement of apparatus and circuitsembodying one form of my invention.

In this figure,

V is an elevated conductor.

M M are transformers.

I1 I2 are respectively the primary and secondary windings of thetransformer M, which may be as desired a step-up or a step-downtransformer.

G0 are condensers.

L L are inductances.

s is a spark gap.

A is an alternating current generator or other suitable source ofelectrical energy.

76 is a key.

The circuit 8 G11 L is a sonorous circuit adapted to develop electricoscillations of a definite frequency when its electrical equilibrium isdisturbed, and the circuit s O L is a sonorous circuit adapted todevelop electric oscillations of frequency equal to those developed bythe circuits 0 11 L.

The function of the coil L is to render the product of the inductancesof the circuit a (J 11 L and the elevated conductor with which saidcircuit is associated, large compared to the square of the mutualinductance between the two circuits, as explained in my hereinbeforementioned Letters Patent. The condenser C is preferably a condenserhaving a dielectric of air, but the condenser C may have a soliddielectric so as to increase the capacity of said condenser per unit ofcubical contents as explained in my application Serial No. 182,541,liled November 2a, 1903.

The ratio of the inductance of the circuit 8 O L L to the capacity ofthe circuit is made relatively large so as to obtain great persistencyof oscillation, but in the circuit .9 C L the ratio of the inductance ofthe coil L to the capacity of the condenser G is made relatively smallby making the capacity of the condenser C relatively large so thatalthough but few oscillations, say four or five, are maintained beforethe amplitude of these oscillations falls to th of its initial value, agreat amount of energy may be stored in the condenser C and therefore agreat amount of energy may be discharged across the spark gap with theresult that the spark produced by the combined discharges of condensersU and C is made larger, or fatter, than if the second sonorous circuit.5- (J L were not employed. In this way the impedance offered by thespark gap to the oscillations developed in the circuit .9 C L L isinitially greatly reduced and therefore the length of the spark may becorrespondingly increased and the amplitude of the oscillations greatlyincreased.

When the spark at s ceases, the system does not cease to vibrate aswould be the case if the circuit .9 C L were not employed, but on thecontrary these oscillations then pass through the circuit 0 C L 0 inshunt to the spark gap .9 and as this circuit is resonant to thefrequency of the oscillations developed by the circuit 8 C I1 L, itoffers to said oscillations no opposition other than that offered by itsohmic resistance, which should be made as small as possible. Theoscillating circuit is now the circuit C 0 C L L 0 L C which has thesame natural period as that of the sonorous circuits .9 C L and s C 11 Las will be apparent from consideration of the factors involved in thedetermination of the period of this circuit. The period of this circuitde- 1 d 6 (L1 L2) which will be seen to be equal to the products C1 L1and C2 L, which products respectively determine the periods of thecircuits 8 C L and s C L L, where C1 02 represent the capacity, and L1L2 the inductance, of these circuits.

I claim 1. In a system of space telegraphy, an elevated cond uctor andmeans for developing electric vibrations of a definite frequencytherein, said means consisting of a sonorous circuit containing a sparkgap and a second sonorous circuit connected across the terminals of saidspark gap, each sonorous circuit being adapted to develop electricalvibrations of said definite frequency. v

2. As a means for developing electric vibrations of definite frequency,two sonorous circuits each attuned to said definite frequency andconnected in parallel to a common spark gap.

3. As a means for increasing the amplitude and the persistency ofelectrical oscillations developed in a sonorous circuit, a circuit ofpends upon the factor 10W ohmic resistance connected across the terminals of the spark gap of the sonorous circuit and resonant to thefrequency of the electrical oscillations developed therein.

4. In a system of space telegraphy, means for developing electricaloscillations of a definite frequency, said means consisting of asonorous circuit containing a spark gap, and means for initiallyreducing the impedance oflered by said spark gap to the oscillationsdeveloped in said sonorous circuit.

5. In a system of space telegraphy, means for developing electricaloscillations of a definite frequency. said means consisting of asonorous circuit containing a spark gap, and means for automaticallydiverting the path of the electrical oscillations developed in saidsonorous circuit from said spark gap without altering the frequency ofsaid oscillations.

6. In a system of space telegraphy, a radiating conductor and means fordeveloping electrical oscillations of a definite frequency therein, saidmeans consisting of two sonorous circuits, each attuned to said definitefrequency, connected in parallel to acommon spark gap.

7. In a system of space telegraphy, a radiating conductor, a sonorouscircuit for developing electrical oscillations therein and means forincreasing the amplitude and the persistency of the electricaloscillations developed in said sonorous circuit.

8. In a system of space telegraphy, a radiating conductor. means forcreating electrical oscillations therein and other means associated withthe first mentioned means for increasing the amplitude and thepersistency of said electrical oscillations.

9. In a system of space telegraphy, a radiating conductor, a sonorouscircuit for creating electrical oscillations therein and means forincreasing the amplitude and persistency of said electricaloscillations, said means consisting of a circuit of low ohmic resistanceconnected across the spark gap of said sonorous circuit and resonant tothe frequency of the electrical oscillations developed in said sonorouscircuit.

10. In a system of space telegraphy, a radiating conductor, means forcreating electrical oscillations therein and other means associated withthe first mentioned means for increasing the persistency of saidelectrical oscillations.

11. In a system of space telegraphy, a radiating conductor, means fordeveloping electrical oscillations of a definite frequency there in,said means consisting of a sonorous circuit containing a spark gap, andmeans for initially reducing the impedance offered by said spark gap tothe oscillations developed in said sonorous circuit.

12. In a system of space telegraphy, a radiating conductor, means fordeveloping electrical oscillations of a definite frequency therein, saidmeans consisting of a sonorous circuit containing a spark gap, and meansfor automatically diverting the path of the electrical oscillationsdeveloped in said sonorous circuit from said spark gap without alteringthe frequency of said oscillations.

13. In a system of space telegraphy, an elevated conductor and means fordeveloping electrical oscillations of definite frequency therein, saidmeans consisting of a sonorous circuit containing a condenser, aninductance coil and a spark gap, and a second sonorous circuitcontaining a condenser, an inductance coil and the aforesaid spark gap,each sonorous circuit being adapted to develop electrical oscillationsof the aforesaid definite frequency.

14. In a system of space telegraphy, means for developing electricaloscillations of a definite frequency, said means consisting of twosonorous circuits, each attuned to said definite frequency and connectedin parallel to a common spark gap, a radiating conductor associated withone of said sonorous circuits and means for rendering the product of theinductance of said last mentioned sonorous circuit and the radiatingconductor large compared to the square of the mutual inductance betweensaid circuit and said radiating conductor.

15. As a means for increasing the amplitude and the persistency ofelectrical oscillations developed in a sonorous circuit, a circuit oflow ohmic resistance, connected across the terminals of the spark gap ofthe sonorous circuit and resonant to the frequency of the oscillationsdeveloped by said sonorous circuit, said circuit of low resistancehaving the ratio of its inductance to its capacity relatively small ascompared with the ratio of the inductance to the capacity of saidsonorous circuit.

16. In a system of space telegraphy, a radiating conductor, a sonorouscircuit associated therewith for creating electrical oscillationstherein, and means for increasing the persistency of the electricaloscillations developed in said sonorous circuit.

17. In a system for developing electromagnetic signal waves of definitefrequency, a plurality of sonorous circuits, each attuned to saiddefinite frequency, means common'to said sonorous circuits forsimultaneously disturbing the electrical equilibrium of said sonorouscircuits, and means for converting the energy of the resultingelectrical oscillations into electroradiant energy.

18. In a system of space telegraphy, two sonorous circuits, each adaptedto develop electrical oscillations of the same definite frequency andconnected in parallel toa common spark gap, a radiating conductorinductively associated with one of said sonorous circuits, and a sourceof periodically varying electromotive force connected to said spark gap.

In testimony whereof I have hereunto subscribed my name this 24th day ofNovember, 1903.

JOHN STONE STONE.

Witnesses:

G. A. HIGGINS, BRAINERD T. JUDKINS.

